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Jack
06-11-08, 03:48 PM
No Haynes to hand at the moment, so can't check myself...

Headlamps - H4's have 3 wires to them; earth, dipped and main, correct?

Does the feed to the dipped beam cut off when the main beam feed goes on? If so, is there any way to preserve that signal with the main beam on? I would like my dipped beam to stay on when I hit main beam on the stalk...

Could I just wire both the main and dipped beam (that goes into the H4 bulb connector) into the main beam lamp?

meritlover
06-11-08, 04:28 PM
yes it does cut-out.

i cant remember if this is a function of the stalk/switch. or the dim-dip relay. probably the latter.

Jack
06-11-08, 04:42 PM
If I chopped the H4 connector off, then connected the main and dipped beam wires together and joined them to the bulb, would that damage the relay?

Spudly
06-11-08, 05:33 PM
Possibly, iirc the flash feed uses both dipped and high beam but dont know if thats a stalk function though but could you not use the feed from there?

Jack
06-11-08, 05:42 PM
No, because I don't want to have to hold the stalk backwards to turn high beam on lol

Welsh Dan
06-11-08, 05:54 PM
You could use a normally open relay between the positive terminals for both bulbs, and use the main beam feed to switch it 'on' to 'closed', so that when main beam is switched on dipped beam is aswell, but dipped beam will also operate on its own. In conjunction with that though I'd run a live feed from the battery to main beam, and use a relay to switch that aswell.... or use a relay with 2 switched pairs to do the job in one.

If you just join the positive terminals they'll all be on or all be off....

meritlover
06-11-08, 06:12 PM
If I chopped the H4 connector off, then connected the main and dipped beam wires together and joined them to the bulb, would that damage the relay?

i wouldnt have thought so, however, your high beam circuit is now driving your highbeam and main beam lamps, and may be over-loading. i woud doubt damages would occur to the relay as that switched contact would be open circuit anyway so wouldnt really be back-feeding anything.

however, i hope that we are still friends

Jack
06-11-08, 07:44 PM
Mr Meritlover you are my bestest friend lol


You could use a normally open relay between the positive terminals for both bulbs, and use the main beam feed to switch it 'on' to 'closed', so that when main beam is switched on dipped beam is aswell, but dipped beam will also operate on its own. In conjunction with that though I'd run a live feed from the battery to main beam, and use a relay to switch that aswell.... or use a relay with 2 switched pairs to do the job in one.

If you just join the positive terminals they'll all be on or all be off....
I've read that 3 times and still need to read it again lol

At the moment I have a relay which takes a switching feed from the full beam wire on the H4 connector to drive the inner lamps (the old cibie lamps had H4 dipped/outer, H1 main/inner). So I think I see what you mean about all being on or all being off.

How about joining the dipped and main beam feeds, then putting a diode in after the relay feed to stop power going back up to the relay and keeping the main beam on?

Like this:

http://i13.photobucket.com/albums/a266/razorjack/Misc/headlamps.gif

Welsh Dan
06-11-08, 07:53 PM
That would work provided you use a suitable diode.

Jack
06-11-08, 07:54 PM
Next question, what would be a suitable diode? The scope of my electrical skillz goes about as far as crimps and solder lol

Welsh Dan
06-11-08, 11:41 PM
Maplin do one that'll take 6 amps.

Jack
07-11-08, 09:26 AM
Something like this? (http://www.maplin.co.uk/Module.aspx?ModuleNo=46413)

meritlover
07-11-08, 10:14 AM
iam still worried about your wiring Mr Jack.
as i have explained you have nearly doubled the load on your high beam circuit.
i dont think the diode is really necessary, but it will not hurt the nova by fitting one.

Welsh Dan
07-11-08, 10:25 AM
Something like this? (http://www.maplin.co.uk/Module.aspx?ModuleNo=46413)

Yes :thumb:.

Jack
07-11-08, 02:31 PM
Cheers Dan, have some rep :D


iam still worried about your wiring Mr Jack.
as i have explained you have nearly doubled the load on your high beam circuit.
i dont think the diode is really necessary, but it will not hurt the nova by fitting one.
Fear not Mr Meritlover, I've had a think about this....

A normal H4 bulb and loom operates one two filaments within each bulb, only one filament at a time. There's no change to that on my planned wiring, as the main beam circuit is supplying a feed to the low beam/outer lamps (as if it was the main beam filament), and a signal wire is used to turn on a relay which has an independent power supply for the main beam/inner lamps. Effectively, the low beam and main beam wiring on the standard loom are still doing the same job, albeit to the same filament instead of to a different one. The main beam lamps are fed exactly as they were when I had the old H4 cibie outer lamps, and everything was a-ok then.

I am thanking you for your concern though :thumb:

loggyboy
07-11-08, 02:46 PM
There is a good reason why the dipped beams cut out, and it has nothing to do with current draw.

Welsh Dan
07-11-08, 03:20 PM
Heat in a H4 bulb?

Jack
07-11-08, 03:52 PM
There is a good reason why the dipped beams cut out, and it has nothing to do with current draw.
:confused: My celica keeps the dipped on when the main beam is turned on.

Or do you mean on H4 bulbs only?

loggyboy
09-11-08, 11:27 PM
Yes H4s only (well twin fillament styles), as WelshDan said, its heat. The halogen (or xenon) gas can only keep the filament from burning out for so long, increasing the heat of both filaments under control for long periods of time will shorten the life. That why 'offroad' high wattage and aftermarket ultrabright lamps dont last long.